Experimental Investigation on High Performance Concrete with Partial Replacement of Cement by Fly Ash and Fully Replacement of Sand by Stone Dust

Transcription

1 International Journal of Constructive Research in Civil Engineering (IJCRCE) Volume 1, Issue 1, June 2015, PP Experimental Investigation on High Performance Concrete with Partial Replacement of Cement by Fly Ash and Fully Replacement of Sand by Stone Dust S.V.V.K.Babu Student of Final Year M.Tech Structural Engineering, Mandava Institute of Engineering and Technology, Andhra Pradesh N.Ch.Anjaneyulu Assistant Professor, Civil Engineering Department of Mandava institute of Engineering and Technology, Andhra Pradesh V.Srinivasa Rao HOD, Civil Engineering Department, Sri vasavi Institute of Engineering and Technology, Andhra Pradesh Abstract: High Performance Concrete (HPC) now a days used widely in the construction industry worldwide. High performance concrete appears to be a better choice for a strong and durable structure. Normal and special materials are used to make these specially designed concrete that must meet a combination of performance requirements. In this project, investigations were carried out on strength properties such as compressive strength, split tensile strength and flexural strength of M40 grade of HPC mixes with different replacement levels such as 25%,30%,35% & 40% of cement by fly ash and 60%,65%,70%,75% &100% of stone dust with sand by adopting water-binder ratio of Super plasticizer (BASF) is used for better workability for high performance concrete. The HPC mix, grade M40 concrete is designed as per IS: IS: , which is conventional. Mechanical characteristics like Compressive strength, Split-tensile strength, Flexural strength were examined. The result of these investigations demonstrates the strength characteristics of stone dust and the properties of fly ash based concrete mixes. Based on the results obtained, the replacement of 100% stone dust and 25% fly ash with 1.2% of super plasticizer which superior characteristics was arrived.the details of the investigations along with the results are presented in this report. Keywords: High Performance Concrete, Fly Ash, M-Sand, Compressive Strength, Split Tensile, Flexural Strength, super plasticizer. 1. INTRODUCTION High performance concrete (HPC) is a concrete that meets special combinations of performance and uniformity requirements which cannot always be achieved routinely using conventional constituents and normal mixing and placing and curing practices. To produce high performance concrete it is generally essential to use chemical and mineral admixtures in addition to the same ingredients, which are generally used for normal concrete. In recent times, many researches are going on for improving the properties of concrete with respect to strength, durability, and performance as a structural material. There are many materials like fly ash, furnace slag, stone dust and silica fume etc. One among these special concrete is the stone dust which is new emerging as one of new generation construction material in producing high strength and performance concrete for special structures. The interest in fly ash and stone dust started in enforcement of air pollution control in many countries. This implies that the industry had to stop releasing fly ash into the atmosphere. To find solution to this problem studies were initiated and after some investigations, it was found that the fly ash and stone dust could be used as a very useful material in concrete. In India, improved stone dust and fly ash is finding its use now a day Need for High Performance Concrete The large scale production of cement has imposed many environmental problems on one hand and unrestricted depletion of natural resources on the other land. This threat to our ecology has led to many investigations in the usage of industrial by- products as supplementary cementations material in making concrete. Another problem in this fast growing world is to encompass the durability and the strength of the concrete structures. High performance concrete (HPC) partakes been developed over the last two decades, and was primarily introduced through private sector architectural design and ARC Page 8

2 S.V.V.K.Babu et al. construction such as high rises and parking garages. By using by- products such as fly ash and stone dust with super plasticizers we can achieve high performance concrete, which possess high workability, high strength, and high modulus of elasticity, high density, high dimensional stability, low permeability and resistance to chemical attack Objectives of this Project To experimentally investigate the effect of replacing 25%,30%,35% & 40% replacement of cement by fly ash and replacement 60%,65%,70%,75%&100% of sand by stone dust on strength characteristics namely compressive strength, flexural strength and split tensile strength. 2. MATERIALS USED 2.1. Cement Ordinary Portland cement-53 grade have used in the investigation. The cement was tested according to IS 4031:1988. It confirmed to IS 12269:1987. Its Properties is given in Table 2.I Table2.1. Show physical property of cement S.NO PROPERTY OF VALUES As per IS:4031 part(i-v)- CEMENT Specific gravity Normal Consistency 30% 30%-35% 4 Initial setting time 90min >30 5 Final setting time 350min <600 6 fineness 1.6% <10% 2.2. Fine Aggregate (IS: 2386 part (I-III)-1963) Clean and dry river sand available locally was used. Sand confirming to Zone-II. Specific gravity and fineness modulus is 2.65 and 3.15 respectively Coarse Aggregate (IS: 2386part (I-III)-1963, IS: 9376) Coarse aggregate passing through 20 mm sieve as given in IS was used for all the specimens. In addition to cement paste- aggregate ratio, aggregate type has a great influence on concrete dimensional stability. S.No Property of aggregate Values As per IS:2386, IS:5640,IS: Specific gravity Sieve analysis Well graded Good 3 Water absorption 0.5% Less than 1.5% 4 Aggregate impact value 15% Less than 30% for concrete 5 Aggregate crushing value 16% Less than 30% for concrete 6 Flakiness & Elongation index 23.4% Less than 25% 2.4. Stone Dust A fine aggregate produced by crushing of stone or natural gravel to be used as an alternate of natural sand is called as Stone dust. The angular shaped stone dust has a good inter locking that gives better binding strength and saves cement. Stone dust is totally inert material and its physical properties are similar to natural sand. Stone dust can be used as a partial or fully replacement for fine aggregate, the use of stone dust as a construction raw material neither imposes risks to the human kind nor to the environment. Specific gravity of Stone dust is 2.65 and fineness modulus is Stone dust is confirming to Zone-III Fly Ash Fly ash is finely divided residue resulting from the combustion of ground or powered coal. The hardened fly ash concrete shows increased strength together with a lower permeability, where the latter leads to a higher resistance towards aggressive admixtures in addition, partial replacement of cement with fly ash reduces the production cost of concrete due to the lower price of fly ash compared to cement. Class F Fly ash (contains less than 20% lime) is collected from Narla Thatha Rao Thermal Power Station (NTPS), Vijayawada. Specific gravity of fly ash 2.30 is and fineness modulus (passing through 45 micro meter) is International Journal of Constructive Research in Civil Engineering (IJCRCE) Page 9

3 Experimental Investigation on High Performance Concrete with Partial Replacement of Cement by Fly Ash and Fully Replacement of Sand by Stone Dust Table2.2. Show chemical property of fly ash class f S.No Chemical properties Compounds (%)Fly Ash-class-F 1 SiO Al2O Fe2O CaO MgO Na 2 O K 2 O Super Plasticizer Super plasticizer BASF, it gives good workability to fresh concrete. 3. MIX DESIGN In this investigation concrete mix design M40 was designed based on IS: , IS: This code presents a generally applicable method for selecting mixture proportion for high strength concrete and optimizing this mixture proportion on basis of trial batches. The method is limited to high strength concrete production using conventional materials and production techniques. Mix Design are given below in table 1. Mix proportioning for the mixes adopted in the study details are given below in tables the mix ratio is 1:0.78:2.43 and w/c is 0.35 is adopted. Mix proportions Cement Fine Aggregate Coarse aggregate W/C METHOD OF EXPERIMENT It is important that the constituent material of concrete remain uniformly distributed within the concrete mass during the various stages of handling and that full compaction is achieved, and making sure that the characteristics of concrete which affect full compaction like consistency, mobility and compatibility are in conformity with relevant codes of practice. The tests were carried out in accordance with relevant IS Standards. The aggregates were tested for physical properties such as specific gravity and particle distribution test. The fresh concrete was subjected to the slump test followed by casting of concrete in moulds for further investigations. All the mixes were prepared by mixing the concrete in laboratory mixer along with water and super plasticizer. For compressive strength 144 NOS cube specimens of size 150 mm x 150 mm x 150 mm, for flexural strength studies, 45 NOS prism specimens of size 100 mm x 100 mm x 500 mm and 45 NOS cylinder specimens of size 300 mm height and 150 mm diameter for split tensile strength studies were prepared. 5. ANALYSIS AND TEST RESULT 5.1. Compression Test After 7 days, 14 days and 28 days of curing, three 150mm cubes of a concrete mixture were tested using the compression machine. These cubes were loaded on their sides during compression testing such that the load was exerted perpendicularly to the direction of casting. The average value of the three cubes was taken as the compressive strength Split Tensile Test The test was carried out by placing the cylindrical specimen horizontally between the loading surfaces of a compression testing machine and load is applied until the initial crack of the specimen occurs, along the diameter Flexural Strength The test was carried out on 100mm Х100mm Х500mm size prism. The test was carried out on a universal testing machine of 400kN capacity, adopting two point loading. The bearing surfaces of the supporting and loading rollers are wiped clean, and any loose sand or other material removed from the surfaces of the specimen. The specimen was placed in the UTM and that the load was applied to the uppermost surface as cast in the mould, along two lines spaced 20cm apart. The load was increased until the specimen fails, and the maximum load applied to the specimen during the test was recorded and appearance of the fractured faces of concrete was noted. International Journal of Constructive Research in Civil Engineering (IJCRCE) Page 10

4 S.V.V.K.Babu et al. Table1. Results for conventional materials mix(c) Compressive Strength (N/mm 2 ) Split tensile strength (N/mm 2 ) Flexural strength (N/mm 2 ) Workability 7 Days 14 Days 28 Days Slump(mm) Table2. Compressive strength (n/mm 2 ) - fly ash 1 C C1-25% C2-30% C3-35% C4-40% Table3. Split tensile strength (n/mm 2 ) - fly ash 1 C C1-25% C2-30% C3-35% C4-40% Table4. Flexural strength (n/mm 2 ) - fly ash 1 C C1-25% C2-30% C3-35% C4-40% Table5. Compressive strength (n/mm 2 ) - stone dust 1 C S1-60% S2-65% S3-70% S4-75% S5-100% Table6. Split Tensile Strength (N/mm 2 ) - Stone Dust 1 C S1-60% S2-65% S3-70% S4-75% S5-100% Table7. Split Tensile Strength (N/mm 2 ) - Stone Dust 1 C S1-60% S2-65% S3-70% S4-75% S5-100% Table8 Wokability Fly Ash Stone Dust S.No Specimen Slump(mm) Specimen Slump(mm) 1 C 30 C 30 2 C1-25% 50 S1-60% 45 3 C2-30% 51 S2-65% 43 4 C3-35% 53 S3-70% 40 5 C4-40% 55 S4-75% S5-100% 35 International Journal of Constructive Research in Civil Engineering (IJCRCE) Page 11

5 Experimental Investigation on High Performance Concrete with Partial Replacement of Cement by Fly Ash and Fully Replacement of Sand by Stone Dust Table9. Final Mix 1:0.35:2.43:0.78 with 25% Fly Ash &100% Stone Dust Compressive Strength (N/mm 2 ) Split Tensile Strength (N/mm 2 ) Flexural Strength Workability (N/mm 2 ) (mm) CONCLUSION In this the Concrete Mix M 40 has been designed as 1:2.43:0.78:0.35. The concrete with optimum replacement percentage of 25% replacement of cement by fly ash and 100% fully replacement of fine aggregate by Stone dust in concrete mix quantities also arrived. The slump value for M40 grade using Stone dust and fly ash gets increased, when 100% replacement of Stone dust and 25% replacement of fly ash with 1.2% super plasticizer. Hence fly ash and stone dust replacement is effective for HPC in order to attain high strength. Compare to nominal concrete M 40 grade concrete attain increase % strength by using lower water/binder ratio. Also reduce the segregation and bleeding. REFERENCES [1] M.V.Rama Raju, K.V.Vivek, Dr. T. Siva Shankar Reddy and P.Srinivas Reddy Study of Properties of SCC using Quarry Dust and Fly Ash University Press; 1986 [2] D.S. Rajendra _rasad, S.M.Maheshwarappa and S. Suresh Effect on Compressive Strength of Replacing Cement by Fly-ash January [3] A.Sivakumar and Prakash M. Characteristic studies on the mechanical properties of quarry dust addition in conventional concrete September, 2011 [4] V.Vishnu (2015) Experimental Investigation on High Performance Concrete with Partial Replacements of Fine Aggregate by M-Sand and Cement by Fly Ash International Journal On Engineering Technology and Sciences IJETS ISSN (P): , ISSN (O): Volume 2 Issue 2, February 2015` [5] V. Sivasundaram and v.m. Malhotra Durability Characteristics studies and mechanical properties of high-volume fly ash concretes june, [6] Ashok Kumar Tiwari and Bandopadhyay (Feb 2002) Pavement quality concrete using blended cements, The Indian Concrete journal, vol.74, pp [7] Nagabhushana and h. Sharada bai Use of crushed rock powder as replacement of fine aggregate in concrete Aug 2011 [8] Swamy RN., Cement replacement material concrete technology and design. Survey, vol.3.london: Univesity Press; [9] Shetty M.S., Concrete Technology Theory and Practice S.Chand & Company Ltd Publisher, [10] Gambhir.M.L, Concrete Technology Theory and Practice Tata Mcgraw hill Education Publisher, [11] IS Indian code of practice for plain and reinforced concrete (fourth version). [12] IS , Specification for the ordinary Portland cement, IS Standard, New Delhi. [13] IS , Specification for fly ash for use as pozzolana and admixture, BIS, Standards, New Delhi. [14] IS , Specification for coarse and fine aggregate from natural sources in concrete, BIS Standards, New Delhi. [15] IS Part 1, Test method for bond strength test, BIS Standards, New Delhi. [16] BS 1881: Part 1: 1983, Method for determination of compressive strength of concrete cubes, Testing Concrete, British Standards Institution, London, International Journal of Constructive Research in Civil Engineering (IJCRCE) Page 12

6 S.V.V.K.Babu et al. AUTHOR S BIOGRAPHY S.V.V.K.Babu got bachelor of technology-civil engineering from JNTU KAKINADA in Sri Vasavi Institute of Engineering and Technology, Nanadamuru, pedana in the year presently studying M.Tech- structural engineering in Mandava institute of engineering and technology, jaggayyapet International Journal of Constructive Research in Civil Engineering (IJCRCE) Page 13